Dual clutch multi-speed transmission

ABSTRACT

A transmission includes an input member, an output transfer gear, first and second shaft or transmission input members, first and second counter shaft members, a plurality of co-planar gear sets, and a plurality of torque transmitting devices. The torque transmitting devices include a plurality of synchronizer assemblies and a dual clutch assembly. The transmission is operable to provide at least one reverse speed ratio and a plurality of forward speed ratios between the input member and the output member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/161,975, filed on Mar. 20, 2009, which is hereby incorporated in itsentirety herein by reference.

TECHNICAL FIELD

The present disclosure relates to transmissions and more particularly toa compact, dual clutch multiple speed transmission having three axes toestablish five or more gear speeds.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may or may not constitute priorart.

A typical multiple speed transmission having countershafts and co-planargear sets uses countershaft gears with a different, dedicated gear pairor set to achieve each forward speed ratio. Accordingly, the totalnumber of gears required in this typical design is two times the numberof forward speeds, plus three for reverse. This necessitates a largenumber of required gear pairs, especially in transmissions that have arelatively large number of forward speed ratios.

While current transmissions achieve their intended purpose, the need fornew and improved transmission configurations which exhibit improvedperformance, especially from the standpoints of efficiency,responsiveness and smoothness and improved packaging, primarily reducedsize and weight, is essentially constant. Accordingly, there is a needin the art for a transmission having improved packaging while providingdesirable gear ratios and torque ranges.

SUMMARY

The present invention provides a transmission having an input member, anoutput member, first and second shaft members, first and secondcountershaft members, a plurality of co-planar gear sets, and aplurality of torque transmitting devices. The torque transmittingdevices include a plurality of synchronizer assemblies and a dual clutchassembly. The transmission is operable to provide at least one reversespeed ratio and a plurality of forward speed ratios between the inputmember and the output transfer gear.

In one aspect of the present invention, the transmission includes fiveco-planar gear sets.

In yet another aspect of the present invention, the transmissionincludes four synchronizer assemblies.

In yet another aspect of the present invention, the four synchronizerassemblies include two one-way synchronizers and two two-waysynchronizers.

In yet another aspect of the present invention, the transmission isoperable to provide at least five forward speed ratios.

In yet another aspect of the present invention, a dual clutchtransmission is provided having a transmission housing, five gear sets,first and second transmission input members, a dual clutch assembly,first and second countershafts and fourth synchronizer assemblies.

In still another aspect of the present invention, the first gear setincludes a first gear in mesh with a second gear. The second gear setincludes a first gear in mesh with a second gear and a third gear inmesh with the second gear. The third gear set includes a first gear inmesh with a second gear. The fourth gear set includes a first gear inmesh with a second gear. The fifth gear set includes a first gear inmesh with a second gear.

In still another aspect of the present invention, the first transmissioninput member has a first end and a second end portion rotatablysupported in the transmission housing. Each of the first gear of thethird, fourth and fifth gear sets are rotatably fixed for commonrotation with the first transmission input member. The secondtransmission input member has a first end portion rotatably supported inthe transmission housing. Each of the first gear of the first and secondgear sets are rotatably fixed for common rotation with the secondtransmission input member. The second transmission input member isconcentric with the first transmission input member and at leastpartially surrounds the first transmission input member.

In still another aspect of the present invention, the dual clutchassembly has a clutch housing connectable to a flywheel of an engine.Moreover, the dual clutch assembly has a first clutch configured toselectively connect the clutch housing to the first transmission inputmember and a second clutch configured to selectively connect the clutchhousing to the second transmission input member. The clutch housing isrotationally supported within the transmission housing.

In still another aspect of the present invention, the first countershaftis rotatably supported within the transmission housing and is spacedapart from and parallel with the first and second transmission inputmembers. The third gear of the second gear set, the second gear of thethird gear set and the second gear of the fifth gear set are eachselectively connectable for common rotation with the first countershaft.The second countershaft is rotatably supported within the transmissionhousing and is spaced apart from and parallel with the first and secondtransmission input members. The second gear of the first gear set, thesecond gear of the second gear set and the second gear of the fourthgear set are each selectively connectable for common rotation with thesecond countershaft.

In still another aspect of the present invention, the first synchronizerassembly is configured to selectively connect the third gear of thesecond gear set to the first countershaft to establish a reverse gearratio when the second clutch of the dual clutch assembly is engaged toconnect the clutch housing of the dual clutch to the second transmissioninput member.

In still another aspect of the present invention, the secondsynchronizer is configured to selectively connect the second gear of thefirst gear set to the second countershaft to establish a second gearratio and the second gear of the second gear set to the secondcountershaft to establish a fourth gear ratio when the second clutch ofthe dual clutch assembly is engaged to connect the clutch housing of thedual clutch to the second transmission input member.

In still another aspect of the present invention, the third synchronizerassembly is configured to selectively connect the second gear of thefifth gear set to the first countershaft to establish a first gear ratioand the second gear of the third gear set to the first countershaft toestablish a third gear ratio when the first clutch of the dual clutchassembly is engaged to connect the clutch housing of the dual clutch tothe first transmission input member.

In still another aspect of the present invention, the fourthsynchronizer assembly is configured to selectively connect the secondgear of the fourth gear set to the second countershaft to establish afifth gear ratio when the first clutch of the dual clutch assembly isengaged to connect the clutch housing of the dual clutch to the firsttransmission input member.

The above features and advantages and other features and advantages ofthe present invention are readily apparent from the following detaileddescription of the best modes for carrying out the invention when takenin connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic view of an embodiment of a transmission inaccordance with the present invention.

DESCRIPTION

Referring to FIG. 1, a multiple speed transmission is generallyindicated by reference number 10. The transmission 10 connectable to anengine input member 12 and has an output member or gear 14. In thepresent embodiment, the input member 12 is a shaft and the output member14 is a gear, however those skilled in the art will appreciate that theinput member 12 may be components other than shafts and the outputmember 14 may be a component, such as a shaft, other than a gear.

The input member 12 is continuously connected with an engine (not shown)or other torque producing machine to provide a driving torque to inputmember 12. The output member or gear 14 rotatably drives a final driveassembly 16. The final drive assembly 16 transfers torque delivered byoutput member 14 to first and second side axles 17, 18, and on to roadwheels (not shown) coupled to side axles 17, 18.

The transmission 10 includes a housing 19 that at least partiallyencloses a gearing arrangement 20. The gearing arrangement 20 includesvarious shafts or members, co-planar intermeshing gear sets, a dualclutch assembly, and selectively engageable synchronizers, as will bedescribed herein. For example, the gearing arrangement 20 includes afirst shaft or transmission input member 22, a second shaft ortransmission input or transmission input member 24, a first countershaft26, and a second countershaft 28. The second shaft or transmission inputor transmission input member 24 is a sleeve shaft that is concentricwith and overlies the first shaft or transmission input member 22. Thefirst countershaft 26 and the second countershaft 28 are each spacedapart from and parallel with the first and second shaft or transmissioninput members 22, 24. The first and second shafts or transmission inputmembers 22, 24 define a first axis of rotation, the first countershaft26 defines a second axis of rotation and the second countershaft 28defines a third axis of rotation. Shaft members 22, 24, the first andsecond countershafts 26, 28 are rotatably supported by bearings 30 a, 30b, 30 c, 30 d, 30 e and 30 f.

A dual clutch assembly 32 is connected between the input member 12 andthe first and second shaft or transmission input members 22, 24. Thedual clutch assembly 32 includes a clutch housing 34 connectable forcommon rotation with the input member 12. Further, the dual clutchassembly 32 has first and second clutch elements or hubs 36 and 38.Clutch elements 36 and 38 together with the clutch housing 34 areconfigured to form a friction clutch, as is known in the art as a dualclutch. More specifically, clutch elements 36, 38 and the clutch housing34 have friction plates mounted thereon or otherwise coupled theretothat interact to form a friction clutch. The clutch element 36 isconnected for common rotation with the first shaft or transmission inputmember 22 and the clutch element 38 is connected for common rotationwith the second shaft or transmission input member 24. Thus, selectiveengagement of clutch element 36 with the clutch housing 34 connects theinput member 12 for common rotation with the first shaft or transmissioninput member 22. Selective engagement of clutch element 38 with theclutch housing 34 connects the input member 12 for common rotation withthe second shaft member 24.

The gearing arrangement 20 also includes a plurality of co-planar,intermeshing gear sets 40, 50, 60, 70 and 80. Co-planar gear set 40includes gear 42 and gear 44. Gear 42 is rotatably fixed and connectedfor common rotation with the second shaft or transmission input member24. Gear 44 is selectively connectable for common rotation with thesecond countershaft member 28 and intermeshes with gear 42. It should beappreciated that gear 42 may be a separate gear structure fixed to thesecond shaft or transmission input member 24 or gear teeth/splinesformed on an outer surface of the second shaft or transmission inputmember 24 without departing from the scope of the present invention.Gear set 40 is disposed adjacent a wall 47 of the transmission housing19 that is on a front or side of the transmission 10 proximate the dualclutch assembly 32.

Co-planar gear set 50 includes gear 52 and gear 54. Gear 52 is rotatablyfixed and connected for common rotation with the second shaft ortransmission input member 24 and intermeshes with gear 54. Gear 54 isselectively connectable for common rotation with the second countershaftmember 28. Gear set 50 is positioned adjacent gear set 40. As will bedescribed in further detail below, co-planar gear set 50 also includes areverse gear 90.

Co-planar gear set 60 includes gear 62 and gear 64. Gear 62 is rotatablyfixed and connected for common rotation with the first shaft ortransmission input member 22 and intermeshes with gear 64. Gear 64 isselectively connectable for common rotation with the first countershaftmember 26. Gear set 60 is disposed adjacent gear set 50.

Co-planar gear set 70 includes gear 72 and gear 74. Gear 72 is rotatablyfixed and connected for common rotation with the first shaft ortransmission input member 22 and intermeshes with gear 74. Gear 74 isselectively connectable for common rotation with the first countershaftmember 26. Gear set 70 is located adjacent gear set 60.

Co-planar gear set 80 includes gear 82 and gear 84. Gear 82 is rotatablyfixed and connected for common rotation with the first shaft ortransmission input member 22 and intermeshes with gear 84. Gear 84 isselectively connectable for common rotation with the first countershaftmember 26 and intermeshes with gear 82. Gear set 80 is positionedbetween gear set 70 and an end wall 88 of the transmission housing 19.

Reverse gear 90 is selectively connectable for common rotation with thefirst countershaft member 26. Reverse gear 90 is axially aligned withand intermeshes with gear 54 of gear set 50. Reverse gear 90 is locatedbetween gear set 60 and end wall 47.

Further, a first countershaft transfer gear 100 is rotatably fixed andconnected for common rotation with the first countershaft member 26. Asecond countershaft transfer gear 110 is rotatably fixed and connectedfor common rotation with the second countershaft member 28. Firstcountershaft transfer gear 100 is configured to mesh with output member14 and the second countershaft transfer gear 110 is also configured tomesh with output member 14, however countershaft transfer gear 110 andcountershaft transfer gear 100 do not mesh with each other. The firstcountershaft transfer gear 100 is located between the co-planar gear set40 and end wall 47. The output gear 110 is located between the co-planargear set 50 and end wall 47. The second countershaft transfer gear 110is located between gear set 50 output member 14.

The transmission 10 further includes a plurality of selectivelyengageable synchronizer assemblies 150, 152, 154 and 156. Synchronizers150 and 156 are a single sided synchronizer that generally includes ashift fork (not shown) that is bi-directionally translated by anactuator (not shown) into either an engaged position or a neutral ordisengaged position. In the present embodiment, synchronizer 150 isselectively actuatable to connect reverse gear 90 for common rotationwith the first countershaft member 26 and synchronizer 156 isselectively actuatable to connect gear 74 for common rotation with thesecond countershaft member 28. In a preferred embodiment, synchronizers150, 156 have only one actuator.

Synchronizers 152 and 154 are double sided synchronizers and generallyinclude a shift fork (not shown) that is bi-directionally translated byan actuator (not shown) into at least two engaged positions and aneutral or disengaged position. In the present embodiment, synchronizer152 is selectively actuatable to connect for common rotation gear 44with the second countershaft 28 and is selectively actuatable to connectfor common rotation gear 54 with the second countershaft 28.Synchronizer 154 is selectively engageable to connect for commonrotation gear 64 with the first countershaft member 26 and isselectively engageable to connect for common rotation gear 84 with thefirst countershaft member 26.

The transmission 10 is capable of transmitting torque from the inputshaft 12 to the output gear 14 in at least five forward torque ratiosand at least one reverse torque ratio. Each of the forward torque ratiosand the reverse torque ratio is attained by selective engagement of thedual clutch assembly 32 and one or more of the synchronizer assemblies150, 152, 154 and 156. Those skilled in the art will readily understandthat a different speed ratio is associated with each torque ratio.

It should be appreciated that each individual gear set 40, 50, 60, 70and 80 provides one or more forward and/or reverse gear ratios uponselective engagement of the synchronizer assemblies 150, 152, 154 and156 and which synchronizer and which gear set are associated with aparticular forward or reverse speed ratio may vary without departingfrom the scope of the present invention.

For example, to establish the reverse torque ratio, clutch element 38 isengaged to couple the clutch housing 34 with the second shaft ortransmission input member 24 and synchronizer 150 is engaged to connectreverse gear 90 to the first countershaft member 26. More specifically,input torque from the input shaft 12 is transferred through the dualclutch assembly 32 to the second shaft or transmission input member 24,through gear 52 to gear 54, through gear 54 to reverse gear 90, from thefirst countershaft member 26 to first countershaft transfer gear 100 andfrom first countershaft transfer gear 100 to the output member 14.

To establish a first forward torque ratio (i.e. a 1st gear), clutchelement 36 is engaged to couple the clutch housing 34 with the firstshaft or transmission input member 22 and synchronizer 154 is activatedto couple gear 80 to the first countershaft member 26. Input torque fromthe input member 12 is transferred through the dual clutch assembly 32to the first shaft or transmission input member 22 to gear 82. Gear 82transfers torque to gear 84 which transfers the torque to the firstcountershaft member 26 and to first countershaft transfer gear 100 andthen from first countershaft transfer gear 100 to the output member 14.

To establish a second forward torque ratio (i.e. a 2nd gear), clutchelement 38 is engaged to couple the clutch housing 34 to the secondshaft or transmission input member 24 which rotates gear 42 andsynchronizer 152 is activated to couple gear 44 to the secondcountershaft member 28. Accordingly, input torque from the input member12 is transferred through the dual clutch assembly 32 to the secondshaft or transmission input member 24, through gear 42 to gear 44,through the second countershaft member 28 to second countershafttransfer gear 110 and then from second countershaft transfer gear 110 tothe output member 14.

To establish a third forward torque ratio (i.e. a 3rd gear), clutchelement 36 is engaged to couple the clutch housing 34 to the first shaftor transmission input member 22 which rotates gear 62 and synchronizer154 is activated to couple gear 64 to the first countershaft member 26.Thus, input torque from the input member 12 is transferred through thedual clutch assembly 32 to the first shaft or transmission input member22, through gear 62 to gear 64, and through the first countershaftmember 26 to first countershaft transfer gear 100 and then from firstcountershaft transfer gear 100 to the output member 14.

To establish a fourth forward torque ratio (i.e. a 4th gear), clutchelement 38 is engaged to couple the clutch housing 34 to the secondshaft or transmission input member 24 which rotates gear 52 andsynchronizer 152 is activated to couple gear 54 to the secondcountershaft member 28. Thus, input torque from the input member 12 istransferred through the dual clutch assembly 32 to the second shaft ortransmission input member 24 to gear 52, then to second countershaftmember 28 through gear 54, then to second countershaft transfer gear 110and then from second countershaft transfer gear 110 to the output member14.

To establish a fifth forward torque ratio (i.e. a 5th gear), clutchelement 36 is engaged to couple the clutch housing 34 to the first shaftor transmission input member 22 which rotates gear 72 and synchronizer156 is engaged to couple gear 74 to the second countershaft member 28.Input torque from the input member 12 is transferred through the dualclutch assembly 32 to the first shaft or transmission input member 22,through gear 72 to gear 74, then through the second countershaft member28 to second countershaft transfer gear 110 and then from secondcountershaft transfer gear 110 to the output member 14

Again, it should be appreciated that any one of the gear sets of gearsets 40, 50, 60, 70 and 80 may be changed to produce a certain forwardand reverse torque ratio without departing from the scope of the presentinvention.

The present invention contemplates that a variety of torque ratios(i.e., the ratio of torque of the output member 14 to the input member12) are achievable through the selection of tooth counts of the gears ofthe transmission 10. This arrangement provides the opportunity toachieve reduced transmission length in comparison with othertransmissions.

While the best modes for carrying out the invention have been describedin detail, those familiar with the art to which this invention relateswill recognize various alternative designs and embodiments forpracticing the invention within the scope of the appended claims.

1. A transmission comprising: a transmission housing; a dual clutchassembly having a clutch housing connectable to a flywheel of an engine,wherein the clutch housing is rotationally supported within thetransmission housing; a first, second, third, fourth, and fifth gearsets, wherein the first gear set includes a first gear in mesh with asecond gear, the second gear set includes a first gear in mesh with asecond gear and a third gear in mesh with the second gear, the thirdgear set includes a first gear in mesh with a second gear, the fourthgear set includes a first gear in mesh with a second gear, the fifthgear set includes a first gear in mesh with a second gear; a firsttransmission input member having a first end portion rotatably supportedin the transmission housing and wherein each of the first gear of thethird, fourth and fifth gear sets are rotatably fixed for commonrotation with the first transmission input member; a second transmissioninput member having a first end portion rotatably supported in thetransmission housing, wherein each of the first gear of the first andsecond gear sets are rotatably fixed for common rotation with the secondtransmission input member and wherein the second transmission inputmember is concentric with the first transmission input member and atleast partially surrounds the first transmission input member; a firstcountershaft rotatably supported within the transmission housing andspaced apart from and parallel with the first and second transmissioninput members, wherein the third gear of the second gear set, the secondgear of the third gear set and the second gear of the fifth gear set areeach selectively connectable for common rotation with the firstcountershaft; a second countershaft rotatably supported within thetransmission housing and spaced apart from and parallel with the firstand second transmission input members, wherein the second gear of thefirst gear set, the second gear of the second gear set and the secondgear of the fourth gear set are each selectively connectable for commonrotation with the second countershaft; four synchronizer assemblies forselectively coupling at least one of the gears of the first, second,third, fourth and fifth gear sets with at least one of the firstcountershaft and the second countershaft, and wherein the selectiveengagement of dual clutch assembly interconnects the dual clutch housingwith at least one of the first and the second transmission input membersand the selective engagement of at least one of the four synchronizerassemblies establishes at least one of five forward speed ratios.
 2. Thetransmission of claim 1 wherein a first of the four synchronizerassemblies selectively connects the third gear of the second gear set tothe first countershaft shaft.
 3. The transmission of claim 2 wherein asecond of the four synchronizer assemblies selectively connects at leastone of the second gear of the first gear set and second gear of thesecond gear set to the second countershaft shaft.
 4. The transmission ofclaim 3 wherein a third of the four synchronizer assemblies selectivelyconnects at least one of the second gear of the third gear set and thesecond gear of the fifth gear set to the first countershaft shaft. 5.The transmission of claim 4 wherein a fourth of the four synchronizerassemblies selectively connects the second gear of the fourth gear setto the second countershaft shaft.
 6. The transmission of claim 1 whereinthe first gear set is adjacent the dual clutch assembly, the second gearset is adjacent the first gear set, the third gear set is adjacent thesecond gear set, the fourth gear set is adjacent the third gear set andthe fifth gear set is between an end wall of the transmission housingand the fourth gear set.
 7. The transmission of claim 1 wherein the dualclutch assembly includes a first clutch and a second clutch, wherein thesecond clutch is configured to selectively connect the clutch housing tothe second transmission input member and wherein the four synchronizerassemblies includes a second synchronizer assembly for selectivelyconnecting the second gear of the first gear set to the secondcountershaft to establish a second gear ratio.
 8. The transmission ofclaim 7 wherein the second clutch of the dual clutch assembly isconfigured to selectively connect the clutch housing to the secondtransmission input member and wherein the second synchronizer of thefour synchronizer assemblies includes is configured to selectivelyconnect the second gear of the second gear set to the secondcountershaft to establish a fourth gear ratio.
 9. The transmission ofclaim 8 wherein the second clutch of the dual clutch assembly isconfigured to selectively connect the clutch housing to the secondtransmission input member and wherein the first synchronizer assembly ofthe four synchronizer assemblies is configured to selectively connectthe third gear of the second gear set to the first countershaft toestablish a reverse gear ratio.
 10. The transmission of claim 9 whereinthe first clutch of the dual clutch is configured to selectively connectthe clutch housing to the first transmission input member and wherein athird synchronizer assembly of the four synchronizer assemblies isconfigured to selectively connect the second gear of the fifth gear setto the first countershaft to establish a first gear ratio.
 11. Thetransmission of claim 10 wherein the first clutch of the dual clutch isconfigured to selectively connect the clutch housing to the firsttransmission input member and wherein the third synchronizer assembly ofthe four synchronizer assemblies is configured to selectively connectthe second gear of the third gear set to the first countershaft toestablish a third gear ratio.
 12. The transmission of claim 11 whereinthe first clutch of the dual clutch is configured to selectively connectthe clutch housing to the first transmission input member and whereinthe fourth synchronizer assembly of the four synchronizer assemblies isconfigured to selectively connect the second gear of the fourth gear setto the second countershaft to establish a fifth gear ratio.
 13. Thetransmission of claim 1 further comprising a first countershaft transfergear fixed to the first countershaft for common rotation with the firstcountershaft and a second countershaft transfer gear fixed to the secondcountershaft for common rotation with the second countershaft andwherein the first and second countershaft transfer gears transfer torquefrom at least one of the first and second countershafts to the outputmember.
 14. The transmission of claim 13 wherein the output member is agear that meshes with the each of the first and second countershafttransfer gears.
 15. A dual clutch transmission comprising: atransmission housing; a first, second, third, fourth, and fifth gearsets, wherein the first gear set includes a first gear in mesh with asecond gear, the second gear set includes a first gear in mesh with asecond gear and a third gear in mesh with the second gear, the thirdgear set includes a first gear in mesh with a second gear, the fourthgear set includes a first gear in mesh with a second gear, the fifthgear set includes a first gear in mesh with a second gear; a firsttransmission input member having a first end and a second end portionrotatably supported in the transmission housing and wherein each of thefirst gear of the third, fourth and fifth gear sets are rotatably fixedfor common rotation with the first transmission input member; a secondtransmission input member having a first end portion rotatably supportedin the transmission housing, wherein each of the first gear of the firstand second gear sets are rotatably fixed for common rotation with thesecond transmission input member and wherein the second transmissioninput member is concentric with the first transmission input member andat least partially surrounds the first transmission input member; a dualclutch assembly having a clutch housing connectable to a flywheel of anengine, a first clutch configured to selectively connect the clutchhousing to the first transmission input member and a second clutchconfigured to selectively connect the clutch housing to the secondtransmission input member and wherein the clutch housing is rotationallysupported within the transmission housing; a first countershaftrotatably supported within the transmission housing and spaced apartfrom and parallel with the first and second transmission input members,wherein the third gear of the second gear set, the second gear of thethird gear set and the second gear of the fifth gear set are eachselectively connectable for common rotation with the first countershaft;a second countershaft rotatably supported within the transmissionhousing and spaced apart from and parallel with the first and secondtransmission input members, wherein the second gear of the first gearset, the second gear of the second gear set and the second gear of thefourth gear set are each selectively connectable for common rotationwith the second countershaft; a first synchronizer assembly configuredto selectively connect the third gear of the second gear set to thefirst countershaft to establish a reverse gear ratio when the secondclutch of the dual clutch assembly is engaged to connect the clutchhousing of the dual clutch to the second transmission input member; asecond synchronizer configured to selectively connect the second gear ofthe first gear set to the second countershaft to establish a second gearratio and the second gear of the second gear set to the secondcountershaft to establish a fourth gear ratio when the second clutch ofthe dual clutch assembly is engaged to connect the clutch housing of thedual clutch to the second transmission input member; a thirdsynchronizer assembly configured to selectively connect the second gearof the fifth gear set to the first countershaft to establish a firstgear ratio and the second gear of the third gear set to the firstcountershaft to establish a third gear ratio when the first clutch ofthe dual clutch assembly is engaged to connect the clutch housing of thedual clutch to the first transmission input member; and a fourthsynchronizer assembly configured to selectively connect the second gearof the fourth gear set to the second countershaft to establish a fifthgear ratio when the first clutch of the dual clutch assembly is engagedto connect the clutch housing of the dual clutch to the firsttransmission input member.